Zero Free Space and Zero Used Space - Can't access disk files

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TestDisk, Data Recovery
TestDisk is powerful free data recovery software! It was primarily designed to help recover lost partitions and/or make non-booting disks bootable again when these symptoms are caused by faulty software, certain types of viruses or human error (such as accidentally deleting a Partition Table). Partition table recovery using TestDisk is really easy.

TestDisk Step By Step to recover lost partitions and repair damaged FAT/NTFS boot sector
Recover deleted files from NTFS partition

NOTE If seeked lost file are still missing, give PhotoRec a try. PhotoRec is a signature based file recovery utility and may be able to recover your data where other methods failed.

PhotoRec is file data recovery software designed to recover lost files including video, documents and archives from hard disks, CD-ROMs, and lost pictures (thus the Photo Recovery name) from digital camera memory. PhotoRec ignores the file system and goes after the underlying data, so it will still work even if your media's file system has been severely damaged or reformatted.
 
It appears that the partitions have been corrupted, you can try what nhasian suggested or a software called "GetDataBack for NTFS", which worked for me in most cases ( it is however not free, so first try the demo to see if it CAN recover the files, if so, you'll have to buy it so it does the actual recovery ).

This software does a sector by sector scan, so no matter how badly corrupted it is, it has a good chance of actually recovering (at least something).